The load-carrying means, usually a forklift, is generally raised and lowered by means of at least one hydraulic cylinder. A control valve is connected within the supply line for the hydraulic cylinder in order optionally to hold a load in a raised position, to raise the load or to lower it. It can arise that when the load is raised an error or a failure of the electrical or the hydraulic supply occurs and the operator is not able to lower the load by actuating the control valve. In this case, a device is necessary to initiate so-called emergency lowering.
It is generally known to arrange a line between the hydraulic cylinder and a tank for the hydraulic medium and to connect a check valve therein which usually closes off the line. The check valve may be actuated manually and may be opened in case of emergency, whereby the raised load is safely lowered and the vehicle is brought into a safe condition. The manual valve is located in a region of the vehicle which can be reached by the operator without the risk of it being inadvertently actuated.
It has become known from DE 199 16 056 A1 to arrange a needle valve in a line which is brought into the closed position under spring bias. An actuating lever arranged in a separate box in the driver cab acts via a traction cable (Bowden cable) on a lever linkage which in turn is connected to the needle valve. By actuating the lever, the needle valve may be brought into the open state in order to effect the emergency lowering.
The object of the invention is to provide a device for the emergency lowering of a load carrying means for a stacker truck which may be easily assembled, requires very little space and may be produced by simple means.